The sessionStorage property allows you to access a session Storage object. sessionStorage is similar to Window.localStorage, the only difference is while data stored in localStorage has no expiration set, data stored in sessionStorage gets cleared when the page session ends. A page session lasts for as long as the browser is open and survives over page reloads and restores. Opening a page in a new tab or window will cause a new session to be initiated, which differs from how session cookies work.

Syntax

// Save data to sessionStorage
sessionStorage.setItem('key', 'value');

// Get saved data from sessionStorage
var data = sessionStorage.getItem('key');

// Remove saved data from sessionStorage
sessionStorage.removeItem('key')

Value

A Storage object.

Example

The following snippet accesses the current domain's session Storage object and adds a data item to it using Storage.setItem().

sessionStorage.setItem('myCat', 'Tom');

The following example autosaves the contents of a text field, and if the browser is accidentally refreshed, restores the text field content so that no writing is lost.

// Get the text field that we're going to track
var field = document.getElementById("field");
 
// See if we have an autosave value
// (this will only happen if the page is accidentally refreshed)
if (sessionStorage.getItem("autosave")) {
  // Restore the contents of the text field
  field.value = sessionStorage.getItem("autosave");
}
 
// Listen for changes in the text field
field.addEventListener("change", function() {
  // And save the results into the session storage object
  sessionStorage.setItem("autosave", field.value);
});

 

Note: Please refer to the Using the Web Storage API article for a full example.

Specifications

Specification Status Comment
Web Storage (Second edition)
The definition of 'sessionStorage' in that specification.
Recommendation  

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
localStorage 4 3.5 8 10.50 4
sessionStorage 5 2 8 10.50 4
Feature Android Firefox Mobile (Gecko) IE Phone Opera Mobile Safari Mobile
Basic support 2.1 ? 8 11 iOS 3.2

All browsers have varying capacity levels for both localStorage and sessionStorage. Here is a detailed rundown of all the storage capacities for various browsers.

Note: since iOS 5.1, Safari Mobile stores localStorage data in the cache folder, which is subject to occasional clean up, at the behest of the OS, typically if space is short.

See also

Document Tags and Contributors

 Contributors to this page: jwhitlock, jccsbenjamin, AlexChao, chrisdavidmills, zbycz, fscholz, ongardie, jsx
 Last updated by: jwhitlock,